You should probably rework the glow animation or whatever you're using. When you shoot the fireball into the sky, it's pretty obvious where the edges of the texture are; it looks way too much like a box.

I just wanted to let you know that I really appreciated the tutorial. It was really simple and easy to follow and it taught me a lot. This is my first time to really learn about what the different maps do and how they work, and you made it a great introduction.